/*
 * Copyright (c) 2020, Andreas Kling <kling@serenityos.org>
 *
 * SPDX-License-Identifier: BSD-2-Clause
 */

#include "MoveTool.h"
#include "Image.h"
#include "ImageEditor.h"
#include "Layer.h"
#include <LibGUI/Action.h>
#include <LibGUI/Menu.h>
#include <LibGUI/Window.h>
#include <LibGfx/Bitmap.h>

namespace PixelPaint {

MoveTool::MoveTool()
{
}

MoveTool::~MoveTool()
{
}

void MoveTool::on_mousedown(Layer* layer, MouseEvent& event)
{
    if (event.image_event().button() == GUI::MouseButton::Right && !m_is_panning) {
        m_is_panning = true;
        m_event_origin = event.raw_event().position();
        m_saved_pan_origin = m_editor->pan_origin();
        m_editor->set_override_cursor(Gfx::StandardCursor::Drag);
        return;
    }

    if (!layer)
        return;

    auto& layer_event = event.layer_event();
    auto& image_event = event.image_event();
    if (layer_event.button() != GUI::MouseButton::Left)
        return;
    if (!layer->rect().contains(layer_event.position()))
        return;
    m_layer_being_moved = *layer;
    m_event_origin = image_event.position();
    m_layer_origin = layer->location();
}

void MoveTool::on_mousemove(Layer* layer, MouseEvent& event)
{
    if (m_is_panning) {
        auto& raw_event = event.raw_event();
        auto delta = raw_event.position() - m_event_origin;
        m_editor->set_pan_origin(m_saved_pan_origin.translated(
            -delta.x(),
            -delta.y()));
        return;
    }

    if (!layer)
        return;

    auto& image_event = event.image_event();
    if (!m_layer_being_moved)
        return;
    auto delta = image_event.position() - m_event_origin;
    m_layer_being_moved->set_location(m_layer_origin.translated(delta));
    m_editor->layers_did_change();
}

void MoveTool::on_mouseup(Layer* layer, MouseEvent& event)
{
    if (event.image_event().button() == GUI::MouseButton::Right && m_is_panning) {
        m_is_panning = false;
        m_editor->set_override_cursor(cursor());
        return;
    }

    if (!layer)
        return;

    auto& layer_event = event.layer_event();
    if (layer_event.button() != GUI::MouseButton::Left)
        return;
    m_layer_being_moved = nullptr;
    m_editor->did_complete_action();
}

void MoveTool::on_keydown(GUI::KeyEvent& event)
{
    if (event.modifiers() != 0)
        return;

    auto* layer = m_editor->active_layer();
    if (!layer)
        return;

    auto new_location = layer->location();

    switch (event.key()) {
    case Key_Up:
        new_location.translate_by(0, -1);
        break;
    case Key_Down:
        new_location.translate_by(0, 1);
        break;
    case Key_Left:
        new_location.translate_by(-1, 0);
        break;
    case Key_Right:
        new_location.translate_by(1, 0);
        break;
    default:
        return;
    }

    layer->set_location(new_location);
    m_editor->layers_did_change();
}

}
